The present invention relates to a rotor for an rotary electrical device suitable as, for example, a rotor for a turbine-driven generator including an air flow path enabling a cooling wind to flow on an electrically conductive member forming an axial end of a rotor coil to be cooled.
The turbine-driven generator includes a stator and the rotor supported on a rotary shaft and facing to the stator. A central iron core of the rotor extends axially and includes a plurality of slots arranged to have a predetermined circumferential distance between adjacent ones thereof so that the electrically conductive members forming the rotor coil are stacked to be received in the slots. The electrically conductive members are fixed to the central iron core by wedges being arranged at a radially outer side of the slots and capable of holding the electrically conductive members at a high rotational speed.
A retaining ring is fitted on the axial end of the rotor coil to be covered through an insulating tube so that the electrically conductive members are held radially by the retaining ring.
In the prior art, since there is no flow path enabling a cooling wind to flow securely in the vicinity of the electrically conductive members under the retaining ring, a temperature of such a position becomes high. As a means for decreasing the temperature at such a position, an air flow groove enabling the cooling wind to flow on the electrically conductive members was proposed, and the air flow groove is formed by a coil support member made of an insulating substance and arranged between the adjacent ones of the electrically conductive members to have the predetermined distance therebetween under the retaining ring so that the cooling wind flows through the air flow groove to cool the electrically conductive members under the retaining ring.
Such prior art is disclosed by JP-A-2000-350412.